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 3 4 5 6   
  <script>
    const arrayOfIntegers = [2, 5, 1, 4, 9, 6, 3, 7];
    const upperBound = 9;
    const lowerBound = 1;

    let sum=upperBound+lowerBound-1
    for (let i = 0; i < arrayOfIntegers.length; i++) {
        let doubel=arrayOfIntegers[i]+arrayOfIntegers[arrayOfIntegers.length-i]
        if (doubel!==sum) {
          
        }
    }
  </script>
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